Radio antenna



1943- L. BARRETT 2,327,163

RADIO ANTENNA Filed Sept. 8, 1941 I i 2 Sheets-Sheet 1 19 19 15 3 Fq'gl. 17 17 fig. 6:

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Aug. 17, 1943. E. 1.. BARRETT RADIO ANTENNA Filed Sept. 8, 1941 2 Sheets-Sheet 2 INVENTOK 1? award L. Barre Z25,

Patented Aug. 17, 1943 UNITED STATES PATENT OFFICE RADEO ANTENNA I Edward L..Ba-rrett, La "Grange, Ill.

Application September 8, 1941, Serial No. 410,024. l 7Claims. ,(o1.25c-ss) This invention relates to a new and improved radio antenna and more particularly toapparatus of this character which-is extensible and retractable by force applied thereto in either direction. j V v v t While they are of broad application, antennae of this character are especially adapted for use in connection with radio receivers used upon automobiles. It is desirable to have th antenna down in its retracted position when the auto.- mobile is in a garage or passing where there are low obstructions, such as tree branches. It is also practical to receive nearby powerful stations with'the antenna in'its retracted position and'many users normally maintain it in' this position, except when traveling at a distance from transmitting stations. Many users, however, prefer to have the antenna normally extended to an intermediate position with its upper end not substantially above the car roof, since this-posi tion is effective for the larger portion of reception requirements and does not require retraction of the antenna when the car enters a garage.

Themajority of suchantennae now in use are manually operated by pulling or pushing on the upper antenna section. In most cases this cannot be conveniently done from inside the car and makes it necessary to stop the car and get out to adjust the antenna. Some antennae are power-operated as, for example, the apparatus shown in my prior Patent No. 2,299,785, October 27, 1942. The construction of the prior application is operable from the interior of the car, which avoids the above-mentioned objection. For some purposes, as stated above, however, it is not desirable to have an antenna which is either fully extended or retracted or which is automatically extended when the radio set is turned on. While a power driven unit can be operated with independent switch control and without limit switches so that it may remain.

at any desired adjustment, there are many installations in which the expense of power operating mechanism is not justified. The actual power necessary to move the antenna is small and it is consequentlyreadily adaptable to remote control by means of'manually operable apparatus.

Antennae, whether power operated or operated by hand by remote control means, should be capable of manual operation by direct grasp of the antenna itself. Both the user and other persons, such as garage attendants or mechanics, will attempt from time to time to raise or lower the antenna in this manner. Consequently, the

antenna and its operating connections must be designed so that they do not jam or get out of adjustment when the antenna is pushed down or pulled up. I

An automobile. radio receiver must be designed with a very high degree of sensitivity, since it operates wit'h'a comparatively small antenna and frequently operates in locations which are shielded and give poor radio reception. 'I'o' function efficiently the input circuit must be matched to the antenna and consequently the antenna should have substantially uniform electrical, characteristics regardless of its position of adjustment.

'It is an object of the present invention to provide a new and improved type ofcollapsible antenna which isadapted for remote control by means of manually operated or power operated means.

It is a further object to provide an antenna of this character which is collapsible and 'extensible by means of force applied directly to the antenna itself.. 1 I

.It is alsoan object to, provide apparatus of this character. which may be freely adjusted to intermediate positions .of extension.

It is an additional object to provide ,an antenna of this type which is smoothly and freely operable by application of relatively light manual power. e '1 It is another object, to provide an antenna having little variation in its electrical .characteristics in difi'erent positions of adjustment and having no substantial variation in such constants with normal wear in use.

It is a further object to provide a construction in whichthe current carrying portions of the antenna are well insulated from the grounded portions of, the structure, with relatively long leakage paths over intermediate insulation.

It isalso" an object to provide a construction which is'simple indesign and adapted for commercial production and use. r

7 Other and further objects will appear as the description proceeds.

I have shown a preferred embodiment of my invention in the accompanying drawings, in which- Figure l is a side elevation of the antenna and operating reel construction} Figure 2 is a view of the construction of Figure 1 as seen from the right;

Figure 3 is a view similar to Figure l but on a reduced scale and showing the antenna in extended'position;

'Figure 4 is a vertical section on an enlarged Figure 5 is a transverse section taken on line 5-5 of Figure 4; and

Figure 6 is a section taken on line 6-8 of Figure 5. p

In the drawings, referring first to Figures 1 to 3, the housing l l encloses the reel or drum and is provided with the strap i2 by which it can be mounted upon any suitable support. This housing I I also is provided with a bushing liithrough which the operating shaft may be connected. Directly connected to the housing H is a tubular fixed antenna housing it, which is provided at its upper end with an insulating washer 65 which supports the lower med section 23 of the antenna proper in spaced relation to the antenna housing it. As shown, the antenna comprises the slidable tubular antenna sections It, ii and I8 and the final antenna section l?! which consists of a solid rod.

Referring now to Figure 42, the lower antenna section 28 is supported at its lower end in the insulating sleeve as, which sleeve is provided at its lower end with a reduced section 2i entering into the housing i i. This section 2! extends well into the drum and providesa lone leakage path between the housing and the antenna. This sleeve is provided with a central cylindrical opening 22 through which passes the flexible member. 23. This member 23 is connected at its upper end to. the lower end of the antenna rod section 19. It will be noted that the lower end of this antenna section i9 is provided with an enlarged portion 25 by means of which it picks-up the second an.- tenna section l8, when the rod moves upwardly. The section i3 is also provided with a shoulder 25 which serves to pick up the next section il. This section ii isprovi'ded with a shoulder 25, serving to pick upthe lower movable section it. The section It is provided with a circumferential bead 21 at its lower end engaging the inner face of the fixed section 23.,so as to prevent play and render the structure substantially -ri'g'id when extended. 1 l

The housing H is formed of metal and has a removable cover 3| as shown in Figures 2 and 5. The housing H has an opening in its side wall through which passes the shaft bearing member 32 which is held in place by nut 33. The hearing- 32 has a shoulder engaging the washer 35 which holds a spring Washer 35 against the insulating member 33. This member 3% may be formed of hard Bakelite or asimilar insulatin material. The member 36 is providedwi'th a plurality of extended portions 37 which engage the inner face of the housing H but the main portion of its surface is spaced from the housing to provide a long leakage path'from the antenna. It is provided with the lug 38 extending through the housing to locate the member positively in the housing. As shown in Figure 6, the member 36 is of a contour to fit within the housing but spaced from the housing walls, and is provided with the channel 53 having a flaring ope'hirig' l-l adapted to receive the flexible member 23. The member 3% is shown in the drawings as reversi'ble, having a second similar channel 42. This reversibility is merely in assembly, so that the reeljc'o'nstruction can be used for right or left hand use, and has no. function in the operation of the assembled reel. 7

The shaft bearing member 32 carries the rotatable reel shaft 144, to the inner end of which are secured the substantially rigid securing washer 45 and the spring washer 45. The latter washer is shoWn as a Belleville spring and serves to frictionally clamp the insulating disc 41 against the fixed washer'fi. These washers 45 and 46 together form a friction clutch engaging the insulating disc 41, permitting slippage in the event of excess pressure from either direction or binding of other parts in operation or in misuse.

. The drum-proper comprises the inner cylindrical wall member 43 and the outer cylindrical wall member d8. These members are spaced apart a distance slightly greater than the thickness of the flexible member 23. Members 48 and 49 are provided with radially extending flanges 50 and 5|, respectively, which are fixedly secured to the insulating disc 41 by means of rivets or eyelets 52. It will be noted from Figure 5 that the outer drum member 49 has its free edge terminating short of the free edge of the member 48. The free edge 53 of member lfi is curved to form an outwardly extendin gflange adapted to receive the flexible member in operation of the apparatus.

'The insulating memberiii isprovided with a aircumferential flange 54 extending opposite the free edge of the outerdrum member 49-.

A-drive member 56, is shown as fitting into a. slot formed in the rotatableshaft 4Q and it will be understoodthat this member 56 may con. nected to a [flexible shaft or to an operating handle of any kind for rotation of the shaft. It will be further understood that the reel may be rotated manually or mechanically by any desired power i rive-,- as the invention is independent of the specific means or method of driv'ingt'he shaft. The housing-memberfl l has an opening formed therein through which extends the shielded cable "63. the conducting member 6 of the cable being shown as soldered at 62 to the lower fixed portion 23 of the antenna. It will be understood that the cable 69, is connected in any desired manner to the radio apparatus using the antenna, v I

a In the use of the-antenna it may be extended and retracted merely by manually applying force to the upper rigid portion E9 of the antenna. When pulled outwardly. the flexible member 23 passes freely from the reel, passing out between the free ends of inner and euter reel members 48 and it will be-understood that in order for this to happen. the reel must rotate, as the inner end of the member 2-3 is fixedly secured to the reel. as indicated by numeral 63, Figure 5. This connection of the flexible member 23' to the drum is located at a point spa ed from the free edgescf drum. If the shaft or other vdrive means connected to the rotating shaft 44 of the drum is free'to perrni-tsuch reverse movement,;the entire assemblywill rotate. If the drive is not reversible, upon drawing 'out the anmnna manually the drum elements #6 and l, .oe -r wi h he nsulatin di c 41, will .s n -ton clutch formed by the I v disc 46, and the shaft and its asse'eiatedparts will remain still. The drive rea ,ed' to one ate the antenna is, Jig-1111 50 that, this friction clutch need, not, have sucha. heavygrip as to cause such manual operation to require an, undue amount of force. --As the antenna is moved upward-1y, the flexible member 28 is guided by meanscftlre channelifi in insulating member te and guided through insulating collar 2-0;. The convolutions progressively move toward the free open end of the drum channel and inteb a noi ubstant al si ta e to th sr m ee.

Similarly, when the antenna is pushed down, the

flexible member 23:is guided in the reverse direction and the convolutions gradually become closer together in the drum. space; Adequate drum area is provided so that there is no bind ing when-theantenna is completely collapsed.

In the operation of the antenna, by rotating the shaft 44 the sections are forced upwardly or drawn downwardly by flexible member23, which feeds out of'or into the reel space between the drums as shaft M is rotated. Continuing to apply power to the shaft after movement is completed in either direction will not injure the parts or cause jamming, since slippage will then occur between the-insulating disc 41 and the associated friction clutch. It is to benoted that the antenna elements and the flexible member 23 are connected in'the electrical input circuit of the receiver with which the antenna is used, and consequently must be H insulated from ground. The insulating disc d1 partially serves this purpose and the insulating member 35 completes insulation within the housing. The collar 29 serves to insulate the lower fixed section of the antenna and the adjacent portion of flexible member 23 from the housings ii and it. The insulating member 36 provides a relatively long leakage path between the point of contact of the member23 therewith and the points of contact between that member 36 and the housing I i. Further, even though the member 23 be lubricated, as it will be in normal use, there is no tendency for this lubricant to flow over insulating surfaces.

The drum surfaces which contact the mem ber 23 are rounded and consequently there is little wear at their points of contact and the apparatus will have long life without deterioration. The capacity between the metal drum members 43 and 49 and the grounded housing members is constant regardless of the portion of member 23 which may be within the reel. The capacity betwen the lower fixed section 23 of the antenna and the housing member I4 is also constant. Therefore, there is very little variation in the capacity of the antenna regardless of its position. The capacity is only slightly higher extended position, because some of the antenna surface is exposed to adjacent car parts, but the capacity within the antenna structure itself is substantially constant.

-While I have shown a preferred embodiment of my invention it is to be understood to be'illustrative, only, as it may be modified to meet differing conditions and requirements, and I contemplate such variations as come within the spirit and scope of the appended claims.

What is claimed is:

1. In combination with a radio antenna comprising flxed'and movable elements, a flexible member connected to the movable element, said flexible member being capable of applying a thrust or a pull to the movable member, a drum having inner and outer substantially cylindrical walls fixedly secured together and spaced apart a distance slightly greater than the thickness of the flexible member, the walls having free edges on one side of the drum, the inner wall having an outwardly extending flange extending axially beyondthe outer wall, the wall edges being spaced apart a distance slightly greater than tli thickness of the flexible member, one end of the flexiblemember being secured to the drum between the walls at a point spaced from their free edges,

and means rotatably supporting the drum.

I. *2. In combination with a radio antenna comprising fixed and movable elements, a flexible member connected to the movable element, said flexible member being capable of applying a thrust or a pull to the movable member, a metallic drum having. innerand outer substantially cylindrical walls fixedly secured together and spaced apart a distance slightly greater than the thickness of the-flexible member, the Walls having free edges on oneside of the drum spaced apart a distance slightly greater than the thickness of the flexible member, one endofthe flex ible member being secured to the drum between the walls at a point spaced from their free, edges, insulating means for guiding the flexible member into the space between the drum walls, and means rotatably supporting the drum. 7

:. 3. In combination with a'radio antenna comprisingfixed and'movable elements, a flexible member connected tothe movable element, said flexible member being capable .of applying a thrust or a pull to the movable member, a drum having inner and outer substantially cylindrical walls fixedly secured together and spaced apart a distance slightly greater than the thickness of the flexible member, the walls having free edges on one side of the drum, the inner wall having an outwardly extending flange extending outwardly over the space between the walls, the wall edges being spaced apart a distance slightly greater than the thickness of the flexible member, one end of the flexible member being secured to the drum between the walls at a point spaced from their free edges, a rotatable shaft for the drum, and a frictional clutch connecting the drum and shaft.

4. In combination with a radio antenna comprising fixed and movable elements, a flexible member connected to the movable element, said flexible member being capable of applying a thrust or a pull to the movable member, a me.- tallic drum having inner and outer substantially cylindrical walls fixedly secured together and spaced apart a distance slightly greater than the thickness of the flexible member, the walls having free edges on one side of the drum spaced apart a distance slightly greater than the thickness of the flexible member, one end of the flexible member being secured to the drum between the walls at a point spaced from their free edges, a rotatable shaft for the drum, and insulating means connecting the shaft and drum.

5. In combination with a radio antenna comprising fixed and movable elements, a flexible member connected to the movable element, said flexible member being capable of applying a thrust or a pull to the movable member, a metallic drum having inner and outer substantially cylindrical walls fixedly secured together and spaced apart a distance slightly greater than the thickness of the flexible member, the walls having free edges on one side of the drum spaced apart a distance slightly greater than the thickness of the flexible member, one end of the flexible member being secured to the drum between the walls at a point spaced from their free edges, a rotatable shaft for the drum, and an insulating disc extending between the drum and shaft, and a frictional driving connection between the shaft and insulating disc.

6. In combination with a radio antenna comprising fixed and movable elements, a flexible member connected to the movable element, said flexible member being capable of applying a thrust or a pull to the movable member, a drum having inner and outer substantially cylindrical metallic walls fixedly secured together and spaced apart a distance slightlygreater than :the thickness of the flexible member, the walls having free edges on'e-ne side of the drum spaced apart. a. distancesli-ghtly greater than the thick-- ness of the flexible member, =.one end of the flexible member being secured to the .drum between the .walls at a 'pcintspaced from their ireeedges, insulating means rotatably supporting the drum, anda housing :for said drumrrsaid housing having an opening therein, insulating means fer guiding the flexible member through the-openingiandinto :the drum, said insulating means substantially closing the opening between the .free edgesef :the drum walls.

"7. In combination with a radio comprising fiXed and movable elements, 3a flexible member connected to the movable element, said "flexible .member being capable of applying a thrust or a pull to the movable member, ame- I tallie drum having inner :and :outer substantially spaced apart is. distance slightly greater than the tlnelmess 101: the flexible member, the walls having tree edges ene iside 10f the drum spaced a m-rt a distanaezslightly greater than the thick rims ;of the flexible member, nne end of the flexible member being rsecured to the .drum between the wallsat a point spaced from their free-edges, a metallic :hnusing for the drum spaced from the drum 'walls, a rotatable shaft carried by the housing, insulating means connecting the shaft and drum, the housing having an opening therein, insulating means carried by the housing for guiding the flexible member through the opening, and an insulating member carried within the musing and eontacting the-housing only at spaced points, the insulating member guiding the flexible member into the drum, :said insulating member being located adjacent -to and substantially closing the npening vbetween the free edges of the drum walls. 7

EDWARD vL. BARRETT. 

